[llvm] [llvm] Fix crash caused by reprocessing complex reductions (PR #122077)

[David Spickett via llvm-commits]

DavidSpickett wrote:

I understand that the motivation for this fix is a Fujitsu test suite regression caught by Linaro (https://linaro.atlassian.net/browse/LLVM-1501), I have pinged the assignee there to check this.

If in the next few days there is another strong reason to go ahead and land this, please do so. Linaro will follow up if there's anything still failing afterwards.

https://github.com/llvm/llvm-project/pull/122077